Double star
Videos
In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes.
The Hubble Telescope's 100,000th capture showing two stars that appear close together. The star on the right is a nearby Milky Way star while the star to the left is a quasar 9 billion light years away. This is an example of an optical double and is due to the quasar's immense luminosity.
Astronomers have mistakenly reported observations of a double star in place of J 900 and a faint star in the constellation of Gemini.
The color-contrastant binary Gamma Andromedae seen by a telescope
Observational astronomy
Videos
Observational astronomy is a division of astronomy that is concerned with recording data about the observable universe, the practice and study of observing celestial objects with the use of telescopes
Mayall telescope at Kitt Peak National Observatory
An assembly in Estonia to observe meteors
Overview of types of observational astronomy by observed wavelengths and their observability.
Ultra HD photography taken at La Silla Observatory